HIV is a virus that is incredibly tough to nail down. It mutates constantly – not enough to lose its deadly aspects, but enough to shapeshift, as it were, preventing our immune systems from recognizing it. That makes a vaccine really difficult to create.

But now the New York Times is reporting that a new combination of experimental vaccines appears to be effective in lowering the risk of HIV infection! In a controlled study, the number of people in a group using the vaccine had 30% fewer HIV cases compared to a group who did not get vaccinated. Specifically, there were 51 HIV cases out of 8200 people vaccinated versus 74 out of 8200 not vaccinated. That’s very heartening! The vaccination course is actually composed of two different vaccines, neither of which on its own was effective, but together appear to boost the immune system enough (in some cases) to help fight off the initial virus infection.

A few things to note:

1) The vaccine course was not 100% effective, and does not drop the viral load of someone already infected. This is a prophylaxis, a preventative. It’s not a cure.

2) There is no HIV in the vaccine itself — it has pieces of the protein HIV coats itself with, to help the body recognize the virus — so people using it cannot get HIV from it.

3) The vaccine is not widely available; it’s still experimental. It was also tested on just strains found in Thailand, which may not translate well for other strains found elsewhere.

4) The vaccination was developed by the U.S. Army in cooperation with the National Institute of Allergy and Infectious Diseases. Expect the antivax cranks to go ballistic over that first part.

I think this is a big stride forward, but as always there’s a ways to go yet. Ask anyone in the medical profession what the most important advance in history has been in their field, and vaccines are very high on the list. Vaccines have saved hundreds of millions of lives… and it looks like scientists will continue to find ways to do so.

Thanks, Phil! Hopefully this research pans out and can advance the area of HIV prevention. It would be nice to see a highly reliable vaccine developed. Granted, the anti-vaxers, with support from fundamentalist religious fearmongers, will be against any such vaccine. It would cause not only autism, but promiscuity as well! Oh noes!!!11!!one!

While I’m optimistic (I generally am), there is along way to go. There were 16000 people in this trial, of that we are talking about a difference between the two groups of people of 23. Even the authors of the NYT article pointed out that this may just be in the noise.

This is very good news. Yes, the numbers are small, at the limit of noise. But against a disease that infects 7500 new people every day, which has had no vaccine despite more than 20 years of research, we need some cautious optimism.

My only wonder about this, and this might be part of my ignorance, but the expected variance for the two data sets, based on Poisson statistics, are 74 +/- 8.6 and 52+/- 7.2, so the groups are not HUGELY disparate above any kind of statistical noise. But you’re right, I heard this on NPR driving to work today, and I almost hit the car in front of me. This is very big news.

2) There is no HIV in the vaccine itself — it has pieces of the protein HIV coats itself with, to help the body recognize the virus — so people using it cannot get HIV from it.

“Vaccination infects people” was the first claim of the local anti-vaxx nuts. Oh yes, we have them too. [/headdesk]

“Sanofi’s ALVAC uses a canarypox virus that’s been disabled so it doesn’t cause sickness in humans to smuggle three HIV genes into the body. It’s designed to coax the immune system to make so-called T-cells, protectors that hunt and kill infection deep inside the body.

The AIDSVAX shot contains an HIV protein called gp120 that’s used by the virus to enter human cells. It is designed to encourage the body to produce neutralizing antibodies to destroy HIV viruses before they can infect healthy cells. [Bloomberg.com]”

HIV is an ssRNA retrovirus of 9 genes coding for 19 proteins. (Small RNA-virus -> likely dense coding, AFAIU.) 3 genes + 1 proteins is at most a 1/3 of a HIV-virus. Not counting for the 4 types or so of enzymes an RNA virus needs to get reverse transcription going. The canarypox virus doesn’t help there, it’s an avipoxvirus, which is a dsDNA virus; all according to Wikipedia.

Btw, Jerome Kim, deputy director of science at the sponsoring Walter Reed Army Institute of Research, is editor of books on HIV protocols. I guess the US army knows its HIV. (o.O)

I always find it interesting how these sorts of numbers are reported. As Phil writes it, there was a 30% reduction in number of cases. That sounds huge!
However, when you look at the number of infections per group, you see that the actual risk of infection goes from 0.902% without vaccine to 0.622% with the vaccine (percentages rounded off). So what you’re left with is a decrease of less than 0.3 percentage points of actual risk of infection. A lot less exciting than 30% (but still good news, probably).

Heartening news, even if it’s about one course of treatment that may or may not pan out in the long run. And who knows what else might be learned from this, even if this treatment turns out to be less effective than others? As Phil has pointed out in other posts, this is how science is done, with incremental steps that add up over time.

Not to say that more dramatic breakthroughs don’t happen. But from what I understand about the history of science, those are pretty rare, or even appear only in retrospect.

I can’t help wondering about the psychosocial component to this. The article states that all participants received condoms and counseling about the risks, but I find it hard to believe that the participants were not at least subconsciously influenced by the idea that they were vaccinated against HIV and could be at a lower risk. Did it make them more likely to engage in risky behavior, or less? It’d be interesting to see a study of the behavioral changes among the participant group versus a group of non-participants.

At last! when aids started in the 80s I though it would wipe out the human race. By the way the conspricy nuts all ready beat you to it Phill on aids seeveral groups calim that the goverment created aids to wipe out minortes.

Like Nick says, it shouldn’t have changed their behavior as they would not know if they were given the vaccine or a placebo, I’m pretty sure they wouldn’t have even known what the percentage of vaccine to placebo even was. If it did that’s some serious gamble to take with no real upside.

Like Nick says, it shouldn’t have changed their behavior as they would not know if they were given the vaccine or a placebo, I’m pretty sure they wouldn’t have even known what the percentage of vaccine to placebo even was. If it did that’s some serious gamble to take with no real upside.
_____________

True, I don’t mean to imply that there would be a difference between those who received the vaccine versus the placebo, since it’s a double-blind study. But all those who participated received counseling and AIDS prevention tips, so I think it’s worth examining how the participants compare with an equivalent sample of 8,200 people who received neither the injection nor the counseling.

If, for example, there were 200 HIV cases in this third group versus 74 in the placebo group and 51 in the vaccine group, then from a public health perspective it might be much more cost-effective to give people condoms, counseling, and a saline shot than the actual vaccine.

Please don’t take that the wrong way. I’m fully supportive of the effort to develop the vaccine. And the past 30 years of fighting AIDS has shown that education and prevention alone hasn’t stopped the spread of the disease. What I’m wondering is if there is some psychological effect of actually receiving a shot to prevent HIV versus simply reading a pamphlet.

I was going to say that despite what antivaxers might say, fragments of HIV can’t cause AIDS. How do we know this? Because, with 19 proteins coded by only 9 genes (see Torbjörn’s comment), HIV is *obviously* irreducibly complex.

I think I’m going to apply to the NSF for a grant to build a SuperConducting SuperLoon Collider. The SCSLC will attempt to smash two groups of Loons together at extremely high energy to see what they are made of. Especially interesting will be colliding Cdesign propentists who are also antivaxers with themselves. I think they will exhibit integral spin (Bose-Einstein Loons), will be their own anti-Loons and will decay into gamma rays. Who says ID doesn’t generate any testable hypotheses?

@Danno(#30):
Well, sort of. Vaccines don’t really “boost the immune system” so much as they wave the critical viral protein segments in front of the immune system like you’d wave a stick in front of a dog, saying “smell that boy? Got it? Got it?” *whip it out of sight* “Fetch!” with the result that the immune system will pounce on the protein segments the next time they’re seen.

Yeah, I know it’s a questionable analogy, but I just couldn’t get the mental image out of my head…

@ Mark: Informed consent rules require that they have the experimental protocol explained to them fully unless there is some very, very, very strong reason not to and the stuff they aren’t told doesn’t pose a danger to them (let me emphasize that experiments that withhold anything, even minor details, are very hard to get approved).

In this case, telling them that there might be a placebo doesn’t change the difference in the outcome between the groups (any change in behavior would be, on average, the same in the two groups), and not telling them can be extraordinarily dangerous, so if they follows human research protocol they would have told the subjects they might be getting a placebo.

@toasterhead
As far as I understand, the incidence rate of those in the trial was the same as the general population. Thus, there doesn’t seem to be any effect where people started to engage in risky behaviors after being vaccinated.

That is always a concern for any trial of this kind, of course. But the best you can do is provide extensive counseling, as was done here.

@9 William Angelo – “Isn’t science wonderful. Having an HIV vaccine, a person can engage in risky behavior and not have to worry about geting sick. And onward humanity goes.”

What you mean like attend accident scenes, work in hospitals, things like that?

/sarcasm on
And then the lord did say, “Cursed be the paramedic in mine sight, for I shall smiteth him down with plagues….and while I’m at it all you dentists can sucketh upon eggs as well, and don’t even get me started on haemophiliacs, I’ve been telling them to repent and stop all that bleeding nonsense for ages but do they listen….Nooooo, well now they shall reap as they have sown, For I am a just and loving God”
And it was so.
sarcasm off/

I actually saw this on the news moments before it hit this blog. I actually didn’t wade into the comments until just now because my tolerance for burning stupid was low today.

Though it would seem the anti-vax crowd is strangely silent. Like a few others have commented it’s definitely a Good Thing (TM), but I’m not getting hopes up just yet .

Oh, and @ William Angelo

If we eradicate STDs then it isn’t “risky behavior” now is it?

Not to imply that you’re saying otherwise Kuhnigget & Cairnos, but no one needs to justify a cure for HIV/AIDS based solely on the people who contracted it through non-sexual or non-drug modes of transmission. I happen to think people who have sex deserve to live. The same goes for IV drug users. Anyone who thinks differently really doesn’t deserve to be part of any conversation involving healthcare or a vision for humanity.

@William Angelo
Yours is the same reaction we got when the Australian government first introduced the HPV vaccination program for all 14-year-old girls in schools: “but if you vaccinate them against possible cervical cancer in the future, it is tantamount to giving them permission to have sex”.

Any preventive measure is worthwhile, not because it changes people’s behaviour, but because it doesn’t.

I blogged about this and the homeopathy story mentioned @Shane today as well.

In 1984, Dr. Robert Gallo promised an AIDS vaccine in 2 years. He was wrong.

In 2008, Dr. Anthony Fauci urged “rethinking” on the vaccine, after another in a series of failures over 24 years:

“Everything is on the table,” Dr. Fauci said at the one-day meeting, a Town Hall-type discussion for vaccine researchers on how best to spend federal H.I.V. vaccine money in light of a budget that has been flat for several years.

“There is not an immediate solution to the problem,” Dr. Fauci said in an interview. But, he also said, the budgetary constraints mean that “we are going to have to justify what we are doing” and determine what steps to take after further discussions in smaller meetings with researchers.”

In 2009, these modest tepid results in Thailand, are merely an effort to “justify what they are doing.”

There are a lot of variables here, and I’m not convinced that 23 people out of 8000 is enough to indicate causation.

I’m glad everyone here seems to be up on interpreting statistics. Not everyone is.

After her chemotherapy, my wife was encouraged by her oncologist to take the wonder drug tamoxifen. The oncologist said that it reduced recurrence of breast cancer by 30%. She sited a study and gave us a brochure. My wife, who had researched the drug somewhat, asked if tamoxifen increases the probability of uterine cancer. According to the brochure, tamoxifen raises the chances of contracting uterine cancer by less than 3%. The risk seemed worth it.

After she had taken the drug for a year, we decided to take a look at the raw numbers, which weren’t in the brochure. Each group had 1700 women, and it was a two-year study. At the end of the two years, 58 of the women in the control (placebo) group had a recurrence of breast cancer, whereas only 42 of the women in the tamoxifen group had a recurrence. This is, indeed, almost a 30% reduction in recurrence.

However, in the control group, only 3 women contracted uterine cancer, whereas 52 women in the tamoxifen group contracted uterine cancer. Using the same math, this tells me that the drug increases the chances of getting uterine cancer by 17 times, or 1700%!

Where did the brochure get less than a 3% increase? Like this: if you take the difference between the two numbers (52 – 3 = 49) and divide that by 1700 (the number of women in the group), you get 2.9%.

How is this justifiable? How can they get away with using different math when calculating intended results, versus calculating undesired side effects? Using the numbers in the same fashion ((58 – 42) / 1700) yields less than a 1% reduction in breast cancer recurrence, but that’s not how you’re supposed to do it.

The raw numbers of this particular study clearly indicated that the risk of uterine cancer far outweighed the risk of breast cancer recurrence, but they mucked with the numbers to say otherwise.

My wife quit taking the drug, found a new oncologist, and has never looked back.

I can’t say enough how glad I am that the raw numbers for this AIDS vaccine study have been made freely available. THAT’s real science. The tamoxifen brochure was clearly a marketing tool, not a document intended for peer review. This AIDS vaccine study, however, is a tentative, but very real, step forward in adding true value to humanity’s body of knowledge.

Excellent, excellent, common sense analysis. Thank you very much for sharing.

The AIDS vaccine has been an unmitigated failure for 25 years now. In the USA, the deaths from AIDS has decreased dramatically, which under Farr’s Law was expected to happen — without any drugs or vaccines.

Now, at the tail end of the epidemic, they are trumpeting a marginal, tentative, very modest success in Thailand.

That’s funny – in 2007, more people on the vaccine got HIV, than people on placebo:

The researchers actually carried out three statistical tests on the data from the trial: intention to treat (ITT), per-protocol and modified intention to treat (mITT) analyses. The first two look at those participants who were enrolled (ITT) or completed the treatments (per-protocol), and so preserve the randomisation of patients. These both failed to show a statistically significant benefit from the vaccine.

The mITT process removed several people from the analysis, both breaking the randomisation and producing a statistically significant result. This might have been useful if the vaccine had a clear benefit, but the published benefit was not 31.2% exactly. Rather the confidence interval for the benefit (the range in which the researchers were confident that the true benefit figure lay) was 1%-52% (or, realistically, 0%).

I didn’t find a single news story that indicated the journalist had actually READ the research paper! Poor show for big media outlets, who should be able to employ proper science journalists.